June 18, 1986. The morning was clear and sunny when a deHavilland DHC-6-300 Twin Otter "Vistaliner" (N76GC) operated by Grand Canyon Airlines departed for it's hour long air tour. On board were 18 passengers, many of whom were Dutch citizens booked through a tour company promoted by American Express. The two crew members were seasoned air tour pilots with several years flying the Grand Canyon.

Less than a mile north of the airport, a Bell 206B Jet Ranger helicopter (N6TC) operated by Helitech Inc. was preparing for a 40 minute tour flight with four passengers. The pilot of the helicopter was also highly experienced.

Both flights proceeded normally on their prescribed air tour flights even though no set regulations or standardized routes existed at the time. All flights within the airspace of Grand Canyon in regards to routes and altitudes were conducted by a "gentleman's agreement" with the various air tour companies. A suggested five hundred foot altitude separation of helicopters and airplanes was the safety cushion.

At about 9:30 AM, the two flights were approaching a geologic formation known as Mencius Temple. The Twin Otter, call sign "Canyon 6" from the west and the Bell Jet Ranger, call sign "Tech 2" from the north. For reasons undetermined to this day, both aircraft collided in a horrific impact at an altitude of 6,500 feet. The collision separated the main rotor mast from the helicopter while the disintegrating rotor blades tore into the Vistaliner's tail section causing it to separate in-flight. Both airplane and helicopter pitched over and fell inverted onto the southwestern slope of Mencius Temple. All 25 persons on both aircraft perished, making this accident the second deadliest air disaster in the Grand Canyon to date.

Unlike the June 30, 1956 accident, the wreckage from this collision was for the most part entirely removed from the national park. The wreckage materials from both airplane and helicopter were taken to a private property location near the town of Tusayan, Arizona and discarded.

During 1990, I was given permission by the land owner to take what I wanted as he was frustrated by the salvage company that never removed the wreckage. Within the debris I found many identifiable personal effects which were overlooked by the initial recovery efforts. I was able to return these items to very grateful surviving family members. The other fragments of wreckage that I have collected and documented provide a tangible historical record to this tragic event in the aviation history of Arizona.

In November 2010, I hiked into the crash site area from the Grand Canyon's North Rim. It was an opportunity to actually see the accident site first hand and to document any remaining wreckage. The crash sites are located on the Tonto Plateau nearly 1,200 feet above the Colorado River and almost 6,000 feet below the canyon's North Rim. The area is designated by the National Park Service as "Wild" since there are no trails, no services, and very few water sources.

This accident was a catalyst event that led the Federal Aviation Administration (FAA) to require that all turbine commercial passenger aircraft be required to have Traffic Collision Avoidance Systems (TCAS) installed. This accident also led the FAA to develop a rules and regulations for standardizing air tour routes and altitudes within the Grand Canyon National Park as well as other selected national park boundaries. The result was an increase in air safety and a reduction of aircraft noise levels within the park.

Finding fragments of window plexiglas in the debris field usually indicates that the aircraft cabin was breached in the collision.

Having previously found evidence that the helicopter main rotor blades tore into the passenger cabin near seat row 7. This window fragment probably came from the left side window on the aft entrance door.

Searching a mid-air collision debris field can be a confusing endeavor when similar aircraft are involved. In the case of a helicopter and airplane, the wreckage materials often have a very different type of structure making separate identification easier.

This aluminum tube assembly was found 1,266 feet north of the main impact site of "Tech 2". The assembly was sheared by a tremendous force at both ends and was bent in the middle. I knew it was not from the Twin Otter since there is no such component on the aircraft.

I researched the Bell 206 helicopter and the components that were primarily affected by the collision. The main rotor head assembly of the Bell 206 has two rods extending to the main rotor head. They are called "Pitch Links".

With the aircraft radome removed during maintenance, this photograph of a Nose Wheel Steering Actuator (circled) illustrates it's location on the Twin Otter.

The steering actuator shown installed on the Twin Otter.

The actuator allows the pilot to turn the nose wheel during ground taxi operations,

The shape of this small fiberglass fragment does not match any component on the Twin Otter, but does match the shapes and bends of the fiberglass engine and transmission cowlings on the Bell 206 Jet Ranger helicopter.

Seconds after the collision, a massive imbalance in the fragmenting rotor blades caused the main rotor assembly to separate. The helicopter rolled inverted into a free-fall of 3,000 feet onto this rocky slope on the eastern edge of Tuna Creek.

Similar to the main impact site of "Canyon 6", the crash site of "Tech 2" is marked by a burn area with small fragments lying on the surface.

A majority of the wreckage was removed shortly after the accident to the dump site on the canyon's South Rim.

Locating the crash site of "Tech 2" was a challenge to find. I knew the impact site would be very small and difficult to find.

After walking the area for a half hour, I began to see reflections of broken glass and debris in the distance.

This flexible wristwatch band was located in the burn area.

The watch band, manufactured in Germany, had numerous patent numbers and wording on each link. There were three passengers from West Germany traveling on "Tech 2" when it collided with "Canyon 6".

This outcrop of boulders caught my attention as I examined the crash site of the air tour helicopter. I began to notice the chipping and scarring on their surfaces. (The summit of Mencius Temple in the background).

In addition to the chips and scarring from the helicopter impact, I also noticed the presence of paint and metallic transfers on the surface of the boulders.

Additional metallic transfer marks were found on an adjacent boulder. The NTSB's accident report failed to mention contact with these boulders.

A piece of blue tinted Plexiglas probably came from one of the small tinted overhead windows on the helicopter.

A small burned logo emblem located at the site was once attached to the top of a passenger's seat belt buckle. The original lettering on the emblem was "bh" for helicopter manufacturer "Bell Helicopter".

This rock cairn located near the crash site of "Tech 2" was placed by Scott Thybony (brother of helicopter pilot John Thybony) during his near disaster solo hike to the site in August 1986.

The trip he made in the middle of summer nearly cost Thybony his life when he ran out of water. Thybony, suffering from severe dehydration was able to find a large section of main rotor blade that was key to the accident investigation.

August 31, 1986, less than three months after the collision at Grand Canyon, Aeromexico Flight 498 with 67 on board collides with a Piper Archer over Cerritos, California. Lives are lost on both aircraft and on the ground.

A series of hearings were conducted by the National Transportation Safety Board (NTSB) in the wake of the accident. Prior aircraft accidents were studied as well as the effects of aircraft noise within the national park.

The end result was the establishment of Special Federal Aviation Regulation 50 (SFAR 50) in March 1987 and the passage of the National Parks Overflights Act in August of that year.

Much like the famous 1956 mid-air collision at Grand Canyon, the 1986 collision also caused politicians in Washington D.C. to act quick.

In December 1986, the FAA proposed rules and guidelines regarding flights over Grand Canyon National Park. Taking into consideration safety and noise reduction, regulated air tour routes and altitudes were established.

Since 1987, both general aviation and commercial operators alike must follow specific routes, altitudes and procedures on this chart while flying over the Grand Canyon.

Today, all turbine powered air tour aircraft flying the Grand Canyon are equipped with the required Traffic Collision Alert System (TCAS).

The advent of TCAS technology, concise communication and a pilot's situational awareness of his/her surroundings are the only safeguards to prevent another tragic collision over the Grand Canyon.